Emulsion composition

Abstract

To provide an emulsion composition having high storage stability while containing a specific component (A): chitin nanofiber and / or surface deacetylated chitin nanofiber.SOLUTION: Components (A) to (C) are combined: component (A) chitin nanofiber and / or surface deacetylated chitin nanofiber, component (B) sclerotium gum, and component (C) nonionic surfactant and / or hydrogenated lecithin.EFFECT OF THE INVENTION: This can provide an emulsion composition having high storage stability while containing chitin nanofiber and / or surface deacetylated chitin nanofiber.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to an emulsion composition containing chitin nanofibers and / or chitin nanofibers having chitosanized surfaces. [Background technology]

[0002] Chitin and chitosan have been reported to have excellent antibacterial properties, moisture retention, biocompatibility, and safety, and have been used in medical materials, medicines, cosmetics, food, textiles, agriculture, water treatment, and other applications.

[0003] Chitin and chitosan are generally insoluble in water, and their use has been limited due to the lack of suitable solvents. However, in recent years, by converting chitin and chitosan into nanofibers, they can be dispersed uniformly in aqueous solvents with relative ease, enabling stable formulation.

[0004] With these improvements in convenience, chitin nanofibers and chitin nanofibers surface-chitosanized are being used in cosmetics for their moisturizing effect. Furthermore, the use of chitin nanofibers and chitosan nanofibers has been reported to have therapeutic and preventive effects on stratum corneum damage such as atopic dermatitis, bedsores, and burns, in addition to their moisturizing effect, and has also been shown to increase the thickness of the skin epithelium (Patent Document 1).

[0005] There have been reports that chitin nanofibers and surface-chitosanized chitin nanofibers can be used as emulsifiers (Patent Document 2), but the level is not sufficient to ensure sufficient stability as an emulsion composition, and in some cases there has been a problem of deterioration in storage stability due to aggregation and separation over time.

[0006] A common way to solve this problem is to use a polymer or a surfactant in combination. Polymers are known to thicken the aqueous phase, preventing separation and improving emulsion stability, as well as to impart a moist feeling and improve skin compatibility. Surfactants are generally known to improve emulsifying properties and effectively prevent separation over time. However, nanofiberized chitin and chitosan are prone to aggregation when used in combination with certain polymers and surfactants. For example, the use of anionic surfactants or polymers can cause significant aggregation, resulting in emulsion stability issues. While the use of nonionic surfactants or polymers can avoid significant reactions, their high-temperature stability and stability over time are not satisfactory. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] WO2012 / 036283 publication [Patent Document 2] Japanese Patent Application Publication No. 2018-187619 Summary of the Invention [Problem to be solved by the invention]

[0008] The present invention has been made in consideration of the above-mentioned conventional technology, and aims to provide an emulsion composition that has excellent storage stability while containing specific component (A) chitin nanofibers and / or surface-chitosanized chitin nanofibers. [Means for solving the problem]

[0009] In order to achieve the above-mentioned object, the inventors conducted extensive research and discovered an emulsion composition that is free from aggregation and has excellent storage stability by combining component (A) chitin nanofibers and / or surface-chitosanized chitin nanofibers, component (B) sclerotium gum, and component (C) nonionic surfactant and / or hydrogenated lecithin. [Effects of the Invention]

[0010] The present invention can provide an emulsion composition that contains chitin nanofibers and / or chitin nanofibers whose surfaces have been modified with chitosan, and that has excellent storage stability. [Brief explanation of the drawings]

[0011] [Figure 1] FIG. 1 is a diagram showing a schematic diagram of the fiber width and fiber length of chitin nanofibers and / or surface-chitosanized chitin nanofibers. DETAILED DESCRIPTION OF THE INVENTION

[0012] The nanofibers referred to in the present invention are fine fibers that have been highly defibrated to an average fiber width of the nano level (nm), and examples thereof include fibrous substances having an average fiber width of 2 nm to 200 nm and a fiber length of 100 nm or more.

[0013] The chitin nanofibers used in the present invention as component (A) are not particularly limited, but examples include chitin nanofibers extracted in the form of ultrafine fibers from chitin obtained from shells such as crab shells. Examples of sizes include fibrous substances with an average fiber width of 2 nm to 200 nm and a fiber length of 1 μm or more. Examples of commercially available products include Marine Nanofiber (registered trademark) Chitin NF (display name: chitin, manufacturer: Marine Nanofiber Co., Ltd.).

[0014] The surface-chitosanized chitin nanofibers (component (A)) used in the present invention are not particularly limited, but examples include those obtained by partially deacetylating the surface of the chitin nanofibers described above by hydrolyzing them with a strong alkali such as sodium hydroxide. The average degree of deacetylation is not particularly limited, but is preferably 20% or more. The average degree of deacetylation can be measured by elemental analysis, conductometric titration, FT-IR, etc. For example, the following formula can be used to calculate the average degree of deacetylation:

[0015]

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[0016] The size of the chitin nanofibers having chitosanized surfaces (component (A)) used in the present invention may be, for example, a fibrous material having an average fiber width of 2 nm to 200 nm and a fiber length of 1 μm or more. An example of a commercially available product is Marine Nanofiber HL-01 (display name: hydrolyzed chitin, manufacturer: Marine Nanofiber Co., Ltd.).

[0017] In the emulsion composition of the present invention, one type of component (A) may be selected and blended, or two or more types may be blended in combination.

[0018] In the emulsion composition of the present invention, the amount of component (A) to be blended is not particularly limited, but from the viewpoint of efficacy, feel during use, etc., it is preferably 0.001 to 0.8 mass %, more preferably 0.002 to 0.5 mass %.

[0019] In order to further enhance dispersibility, the component (A) used in the present invention may be mechanically defibrated by high pressure treatment or the like, either before or after use in the formulation.

[0020] The component (B) sclerotium gum used in the present invention is derived from Sclerotium rolfsii and is a polysaccharide composed mainly of glucose monomers. Examples of commercially available products include Amigel (display name: sclerotium gum, manufacturer: Alban Muller International).

[0021] In the emulsion composition of the present invention, the amount of component (B) is not particularly limited, but from the viewpoint of stability, it is preferably 0.001 to 2% by mass of the total amount of the composition, and particularly preferably 0.005 to 1.5% by mass.

[0022] The nonionic surfactant (C) used in the present invention refers to a surfactant that does not have an ionic site in the molecule. The type of nonionic surfactant is not particularly limited, and examples thereof include sorbitan fatty acid esters such as sorbitan sesquioleate and sorbitan isostearate, polyoxyalkylene alkyl ethers such as polyoxyethylene lauryl ether, polyoxyalkylene hydrogenated castor oils such as polyoxyethylene hydrogenated castor oil, polyoxyethylene phytosterols such as polyoxyethylene polyoxypropylene phytosterol, polyoxyalkylene fatty acid sorbitans such as polyoxyethylene sorbitan monostearate and polyoxyethylene sorbitan monooleate, sucrose fatty acid esters such as sucrose stearate, fatty acid polyoxyalkylene glyceryls such as polyoxyethylene glyceryl isostearate, glycerin fatty acid esters such as glyceryl monostearate, glyceryl diisostearate, and poly(2-10)glyceryl diisostearate, polyether-modified silicones such as polyoxyethylene dimethylsiloxane, and polyoxyethylene fatty acid esters such as polyethylene glycol monostearate.

[0023] Among these nonionic surfactants, from the viewpoint of stability over time and feeling in use, there are no particular limitations on the HLB value, but those with an HLB value of 4 to 17 are preferred. Specific examples include PEG-60 glyceryl isostearate, PEG-5 stearate, PEG-50 hydrogenated castor oil, and sorbitan sesquioleate. The HLB value can be calculated using the following formula:

[0024]

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[0025] The hydrogenated lecithin (C) used in the present invention is a lecithin derivative obtained by hydrogenating lecithin, and is also called hydrogenated lecithin. Examples of hydrogenated lecithin include natural phospholipids such as egg yolk lecithin and soybean lecithin, and hydrogenated soybean lecithin, hydrogenated egg yolk lecithin, and lysolecithin, which are lecithin whose unsaturated carbon chains have been converted to saturated bonds by hydrogenation.

[0026] In the emulsion composition of the present invention, one type of component (C) may be selected and blended, or two or more types may be blended in combination.

[0027] In the emulsion composition of the present invention, the amount of component (C) to be blended is not particularly limited, but from the viewpoints of usability and stability, it is preferably 0.05 to 5% by mass of the total amount of the composition. 0.3 to 3% by mass is particularly preferred. Blending within this range will improve emulsion stability.

[0028] The emulsion composition of the present invention refers to a composition in which oil and water are mixed and homogeneously by the use of surfactants or other emulsifying ingredients, regardless of viscosity or form. For example, in the case of cosmetic formulations, this applies to cloudy lotions, emulsions, creams, sunscreens, bath additives, makeup bases, foundations, medicated creams, etc.

[0029] The emulsion composition of the present invention may also contain, as needed, ingredients commonly used in cosmetics and quasi-drugs, such as polyhydric alcohols, lower alcohols, pH adjusters, preservatives, chelating agents, medicinal ingredients, oils, silicones, antioxidants, UV absorbers, UV scattering agents, powders, fragrances, colorants, etc., within qualitative and quantitative ranges that do not impair the effects of the present invention. The blending ratios of these ingredients, when included, can be appropriately selected depending on their types and purposes, and one kind may be used alone, or two or more kinds may be used in appropriate combination. [Example]

[0030] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples. The preparation method is as follows. 1: Heat and dissolve the oily ingredients. 2: The aqueous ingredients are mixed uniformly with the water phase. 3: Component (B) is swelled in water in advance to form an aqueous solution, which is then homogenized with the aqueous phase homogenized in 2. 4: Add the oil phase heated to 70-80°C to the water phase also heated to 70-80°C and stir until homogenous. 5: Process in a homomixer (PRIMIX) at 6000 rpm for 1 minute. 6: Cool to 40°C or below to obtain the formulation.

[0031] For Examples 1 to 13, Comparative Examples 1 to 11, and Reference Examples 1 and 2, the storage stability (aggregation, separation) was evaluated using emulsion compositions having the formulations shown in Tables 1 and 2 below by the following evaluation method.

[0032] [Table 1] *1 Chitosan-surfaced nanofiber: ingredient name: hydrolyzed chitin *2 Chitin nanofiber: ingredient name: chitin powder *3 PEG-60 glyceryl isostearate HLB:16 *4 PEG-50 hydrogenated castor oil HLB:13 *5 PEG-5 stearate HLB:8 *6 Polyglyceryl stearate 10 HLB: 14 *7 Sorbitan sesquioleate HLB:6 *8 Hydrogenated lecithin HLB:9

[0033] [Table 2] *1 Chitosan-surfaced nanofiber: ingredient name: hydrolyzed chitin *2 Chitin nanofiber: ingredient name: chitin powder *3 PEG-60 glyceryl isostearate HLB:16 *5 PEG-5 stearate HLB:8

[0034] The storage stability of the prepared emulsion composition was evaluated. [Evaluation criteria for storage stability (aggregation)] The emulsion compositions prepared using the formulations of the Examples shown in Table 1 and the formulations of the Comparative Examples and Reference Examples shown in Table 2 were stored in airtight containers, and the appearances were evaluated on the day after preparation according to the following criteria. For the evaluation, 0.1 g of the formulation was pressed onto a glass slide to a diameter of 1 cm, and the state of appearance was confirmed. ⊚: No aggregation observed. ◯: Slight aggregation is observed, but it is at a level that does not pose a quality problem. ×: Significant aggregation occurs, at a level that poses a quality problem. [Evaluation criteria for storage stability (separation)] The emulsion compositions prepared using the formulations of the Examples shown in Table 1 and the formulations of the Comparative Examples and Reference Examples shown in Table 2 were stored at 60°C for 1 week, and then their appearances were evaluated according to the following criteria. 10 g of the formulation was weighed into a straight cylindrical transparent glass vial (internal diameter 3Φ x height 5 mm), and the length L (mm) from the bottom to the liquid surface and the length Lb (mm) from the bottom to the liquid surface of the clear layer formed by separation were calculated, and the degree of separation was evaluated using the following formula. Note that a degree of separation of 0% is desirable, so 0% is considered pass, and 1% or more is considered separation.

[0035]

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[0036] The results in Table 1 show that Examples 1 to 13 had excellent storage stability in terms of aggregation and separation. Although Example 2 contained a larger amount of Component A than Example 1, the storage stability was good. Looking at Examples 3 to 13, it was found that the storage stability was excellent as long as the composition described in the present application was used, regardless of the blending amount of Component B or the type and amount of Component C.

[0037] On the other hand, the typical water-soluble thickeners in Comparative Examples 2 to 9 shown in Table 2 tended to aggregate and separate with chitin fiber, resulting in poor storage stability. However, when sclerotium gum was used in Examples 1 to 13 shown in Table 1, aggregation with component (A) and separation over time were almost completely eliminated, dramatically improving stability. Even using a nonionic polymer that is less reactive with component (A) did not necessarily improve stability. The objective of the present invention was achieved only when component (B) sclerotium gum was used, demonstrating that component (B) is particularly excellent in combination with component (A). Furthermore, in Comparative Examples 10 and 11, which contained a component that contributes to surfactant properties similar to component (C), aggregation occurred, which led to separation and resulted in poor stability. These results also demonstrate that component (C) described in the present application is an excellent combination with component (A). Reference Example 1 is a composition that does not contain component (A) and contains an anionic polymer, but compared to Comparative Example 6, which contains component (A), it is clear that the inclusion of component (A) deteriorates the stability. Reference Example 2 is a composition that does not contain component (A) and contains a nonionic polymer, but compared to Comparative Example 4, which contains component (A), it was found that the stability tended to be slightly worse due to component (A). This result also shows that component (A) does not improve stability. Furthermore, for example, between Example 1 and Comparative Example 4, Comparative Example 4 has a higher viscosity, but its stability is not better. Therefore, stability is not determined solely by viscosity. The above results also demonstrate that the stability of the emulsion composition containing component (A) is significantly improved by the configuration described in the present application.

[0038] Compositions of each formulation were prepared in a conventional manner, and it was confirmed that the effects of the present invention were achieved in all formulations.

[0039] Cloudy lotion Ingredients Amount (%) Surface chitosan nanofiber 0.1 Sclerotium Gum 0.05 Pentylene glycol 1.0 Glycerin 7.5 1,3-butylene glycol 8.0 PEG-50 Hydrogenated Castor Oil (HLB:13) 0.05 Hydrogenated lecithin (HLB:9) 0.45 Caprylic / Capric Triglyceride 0.75 Diphenylsiloxyphenyl Trimethicone 0.15 2-phenoxyethanol 0.3 Stabilizer (appropriate amount) Purified water remainder

[0040] Gel Ingredients Amount (%) Surface chitosan nanofiber 0.1 Sclerotium Gum 1.0 Pentylene glycol 1.0 Glycerin 7.5 1,3-butylene glycol 8.0 PEG-50 Hydrogenated Castor Oil (HLB:13) 0.1 Hydrogenated lecithin (HLB:9) 0.9 Caprylic / Capric Triglyceride 1.5 Diphenylsiloxyphenyl Trimethicone 0.3 2-phenoxyethanol 0.3 Stabilizer (appropriate amount) Purified water remainder

[0041] emulsion Ingredients Amount (%) Surface chitosan nanofiber 0.2 Sclerotium Gum 0.5 Pentylene glycol 1.0 1,2-Hexanediol 0.5 Pullulan 0.3 Glycosyltrehalose 1.4 Hydrogenated starch hydrolysate 0.8 Allantoin 0.2 Glycerin 7.5 1,3-butylene glycol 8.0 Isostearic acid PEG-60 glyceryl (HLB:16) 0.4 PEG-5 stearate (HLB:8) 0.9 Cholesterol 0.4 Ceramide 3 0.01 Triisostearin 0.5 Caprylic / Capric Triglyceride 3.5 Cetyl ethylhexanoate 2.0 Hydrogenated Polyisobutene 2.0 Glyceryl stearate 0.5 Squalane 1.0 Behenyl alcohol 0.7 2-phenoxyethanol 0.3 Iodopropynyl butylcarbamate 0.002 Lactobacillus / Rice Fermentation 0.396 Maltitol 0.1 Arginine 0.004 Sodium Dilauramidoglutamide Lysine 0.001 Trimethylglycine 0.1 3-O-Ethyl ascorbic acid 0.01 Trisodium Ascorbyl Palmitate Phosphate 0.001 Niacinamide 5.0 Stearyl glycyrrhetinate 0.05 Tremella fuciformis polysaccharide 0.02 Wisteria sinensis leaf extract 0.1 Peppermint extract 0.1 Tabebuia impetiginosa bark extract 0.2 Tea leaf extract 0.001 Magnesium chloride 0.001 Purified water remainder

[0042] cream Ingredients Amount (%) Surface chitosan nanofiber 0.2 Sclerotium Gum 0.5 Pentylene glycol 1.0 1,2-Hexanediol 0.5 Glycosyltrehalose 1.4 Hydrogenated starch hydrolysate 0.8 Allantoin 0.2 Glycerin 7.5 1,3-butylene glycol 8.0 Isostearic acid PEG-60 glyceryl (HLB: 16) 0.6 PEG-5 stearate (HLB:8) 1.2 Cholesterol 0.4 Macadamia nut fatty acid phytosteryl 2.0 Lauroyl glutamic acid Di(octyldodecyl / Phytosteryl / Behenyl) 1.0 Ceramide 2 0.01 Triisostearin 2.5 Caprylic / Capric Triglyceride 5.5 Cetyl ethylhexanoate 2.0 Hydrogenated polyisobutene 4.0 Glyceryl Behenate 1.5 Squalane 1.0 Vaseline 1.0 Behenyl Alcohol 2.2 2-phenoxyethanol 0.3 Iodopropynyl butylcarbamate 0.002 Lactobacillus / Rice Fermentation 0.396 Maltitol 0.1 Arginine 0.004 Niacinamide 5.0 Stearyl glycyrrhetinate 0.05 Tremella fuciformis polysaccharide 0.02 Wisteria sinensis leaf extract 0.1 Peppermint extract 0.1 Tabebuia impetiginosa bark extract 0.2 Tea leaf extract 0.001 Magnesium chloride 0.001 Hydrolyzed Cassava Tuber Extract 0.1 Acrylates copolymer 0.1 Ethanol 0.1 Sodium Hyaluronate 0.001 Ascorbyl glucoside 0.001 Ascorbyl Tetrahexyldecanoate 0.5 Purified water remainder

[0043] sunscreen Ingredients Amount (%) Surface chitosan nanofiber 0.2 Sclerotium Gum 0.5 Pentylene glycol 1.0 1,2-Hexanediol 0.5 Glycosyltrehalose 1.4 Hydrogenated starch hydrolysate 0.8 Allantoin 0.2 Glycerin 7.5 1,3-butylene glycol 8.0 PEG-50 Hydrogenated Castor Oil (HLB:13) 1.5 PEG-5 stearate (HLB:8) 0.9 Sorbitan sesquioleate (HLB:6) 1.0 Ethylhexyl methoxycinnamate 4.0 Bis-ethylhexyloxyphenol Methoxyphenyltriazine 0.5 Diethylaminohydroxybenzoyl Hexyl benzoate 0.5 Ethylhexyl triazone 0.3 Octocrylene 0.2 Neopentyl glycol diethylhexanoate 5.0 Cetyl ethylhexanoate 3.0 Glyceryl stearate (HLB:6) 0.7 Stearic acid 0.8 Behenyl Alcohol 1.0 2-phenoxyethanol 0.3 Iodopropynyl butylcarbamate 0.002 Lactobacillus / Rice Fermentation 0.396 Maltitol 0.1 Arginine 0.004 Sodium Dilauramidoglutamide Lysine 0.001 Niacinamide 5.0 Stearyl glycyrrhetinate 0.05 Tremella fuciformis polysaccharide 0.02 Wisteria sinensis leaf extract 0.1 Peppermint extract 0.1 Tabebuia impetiginosa bark extract 0.2 Tea leaf extract 0.001 Magnesium chloride 0.001 Titanium dioxide 0.5 Zinc oxide 0.1 Stabilizer (appropriate amount) Purified water remainder

[0044] Bath Essence Ingredients Amount (%) Surface chitosan nanofiber 0.5 Sclerotium Gum 0.3 1,3-butylene glycol 8.0 Rice bran oil 20.0 Mineral oil 10.0 Polybutene 2.0 Polyoxyethylene Polyoxypropylene Cetyl ether (HLB: 14) 2.0 PEG-50 Hydrogenated Castor Oil (HLB:13) 1.0 PPG-6 Decyl Tetradeceth-20 (HLB:10) 2.0 DPG 2.0 Fragrance 0.5 Sodium benzoate 0.3 Purified water remainder [Industrial Applicability]

[0045] The present invention can be used as an emulsion composition having excellent stability, which contains chitin nanofibers and chitin nanofibers surface-chitosanized.

Claims

1. The following components (A), (B), and (C) Component (A): 0.001 to 0.8% by mass of one or more selected from chitin nanofibers and surface-chitosanized chitin nanofibers Component (B) sclerotium gum 0.001 to 2.0% by mass Component (C): 0.3 to 3.0% by mass of one or more selected from nonionic surfactants and hydrogenated lecithin An emulsion composition comprising:

2. 2. The emulsion composition according to claim 1, which is an oil-in-water type emulsion composition.

3. 3. The emulsion composition according to claim 1, wherein the HLB of the nonionic surfactant (C) is 4 to 17.

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